After having my bike put back together (by a mechanic), I notice that one of my front calipers drags a bit (I can hear it when pushing the bike around). I thought that it would loosen after a bit of riding, but it didn't.

Here are other symptoms: The bike leans left when off handlebars, at slow speed resists turning right, and under hard braking the handlebar wants to turn left. Are all of these symptom indicative of the same problem (stuck caliper) and/or should I look elsewhere (alignment)?

 

Just throwing this out, maybe the brakes weren't properly bled?

 

Sounds like an alignment problem to me. Take it back to your mechanic and have him check it out.

 

Scheduled to have him look at it in a couple of days. I don't feel comfortable on it, and will refrain from riding until then.

Brakes were fine prior to my crash...come to think of it, it did seem to pull a bit prior. I may have him look at the calipers too.

 

Turns out that the new wheel I put on has warped rotors, which would explain the braking issue. If the bike wants to go left, can anyone tell me which is the worst offender (left or right rotor)?

Is there a way to check the new rotors before I put then on and do the "spin test"?

 

After giving this some thought...I may have a warped rotor, but it still doesn't seem to be the reason for the bike pulling left. Shouldn't I feel the brake pulsate if the rotor is warped?? I don't but I do notice that the lever goes about 1/2 before I get any appreciable stopping power. Anyone have anything to offer that I should take a look at??

 

hey jaybird,
please tell me what happened prior to all this...sounds like you had a crash and had to get it all fixed up?
mang if you were around here i'd say bring it by so we can take a look at it.

now...you said something about bike doesn't want to go right...
i'm assuming this is not during braking right? firstly check your alignment and suspension setting to make sure it's the same on both sides. if one side is softer than the other, you'll have different feels for going right or left, and when braking, the bike will pull to the softer side...so before any brake work, check suspension and alignment since you had a crash.

then move on to brakes.

here are a few things...
1. the brakes will drag when you're pushing it around. spinning front wheel will get you like 1.5 revolutions or so max. but at least 1 revolution, otherwise it's stuck.
2. you're right, brakes will pulsate if your rotors are warped, not pull.
having a piston that doesn't work will make the bike pull in the opposite direction of piston. having one that works too hard or sticks will make you pull in the same direction of piston.
3. sounds to me like you have a stuck piston. you'll need to take the pads off and extend the pistons one at a time (just put a piece of wood or something in there to prevent one side from coming out. then clean the gunk off the extended pistons...then repeat for the other side. this gunk causes the piston to stick. that's why i bleed my brakes at least 1/year.
4. I've read that some Nissin calipers have issues with sticking. none of my friends' F4is had any issues...mine did, i rebuilt a second pair, and now they're good...but need new rotors (off topic thought).

let me know what you find.

 

I suspect junk in the calipers too. I did have a crash and had the fork oil replaced during the straigtening process. I hope like hell the levels are consistent, but I doubt that it would cause the bars to want to turn under hard braking like it does now. Agree/Disagree?

What do you mean when you say check alignment??

Thanks for letting me know that the dragging is normal. I though it should not drag at all, just a close fit. I would've thought that the mechanic would have shared that with me.

He says: Get new rotors and THEN he will check to see if the axle is bent. So I got another axle from a board member after he fussed about putting the old one back in. After seeing the slight warpage in the rotors he feels he's found the reason for the alignment and braking problems and didn't bother swapping them out.

Can say he's wrong, but I don't know enough to troubleshoot this on my own. Please address the above.

Signed,
Costing Me Fun and Time

 

well...if it wants to turn during hard braking, it's usually indicative that one side of the brake is grabbing harder than the other. but having different fork settings will also do this... you brake, the forks compress at different rates...so one side pulls harder. yes, warped rotors will do this too as one side is grabbing consistently and the other side isn't.

as for alignment...just make sure the forks are straight and it's clamped correctly at the triples...but i don't think that is the case. i would focus on the other two for now.

 

Here's a thought...What if it's the rear? The front suspension looks OK (same settings). The chain adjusters look off a little by eyeball. How do I measure?